xref: /openbmc/u-boot/lib/crc32.c (revision e77e65df)
1 /*
2  * This file is derived from crc32.c from the zlib-1.1.3 distribution
3  * by Jean-loup Gailly and Mark Adler.
4  */
5 
6 /* crc32.c -- compute the CRC-32 of a data stream
7  * Copyright (C) 1995-1998 Mark Adler
8  * For conditions of distribution and use, see copyright notice in zlib.h
9  */
10 
11 #ifdef USE_HOSTCC
12 #include <arpa/inet.h>
13 #else
14 #include <common.h>
15 #endif
16 #include <compiler.h>
17 #include <u-boot/crc.h>
18 
19 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
20 #include <watchdog.h>
21 #endif
22 #include "u-boot/zlib.h"
23 
24 #define local static
25 #define ZEXPORT	/* empty */
26 
27 #define tole(x) cpu_to_le32(x)
28 
29 #ifdef DYNAMIC_CRC_TABLE
30 
31 local int crc_table_empty = 1;
32 local uint32_t crc_table[256];
33 local void make_crc_table OF((void));
34 
35 /*
36   Generate a table for a byte-wise 32-bit CRC calculation on the polynomial:
37   x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x+1.
38 
39   Polynomials over GF(2) are represented in binary, one bit per coefficient,
40   with the lowest powers in the most significant bit.  Then adding polynomials
41   is just exclusive-or, and multiplying a polynomial by x is a right shift by
42   one.  If we call the above polynomial p, and represent a byte as the
43   polynomial q, also with the lowest power in the most significant bit (so the
44   byte 0xb1 is the polynomial x^7+x^3+x+1), then the CRC is (q*x^32) mod p,
45   where a mod b means the remainder after dividing a by b.
46 
47   This calculation is done using the shift-register method of multiplying and
48   taking the remainder.  The register is initialized to zero, and for each
49   incoming bit, x^32 is added mod p to the register if the bit is a one (where
50   x^32 mod p is p+x^32 = x^26+...+1), and the register is multiplied mod p by
51   x (which is shifting right by one and adding x^32 mod p if the bit shifted
52   out is a one).  We start with the highest power (least significant bit) of
53   q and repeat for all eight bits of q.
54 
55   The table is simply the CRC of all possible eight bit values.  This is all
56   the information needed to generate CRC's on data a byte at a time for all
57   combinations of CRC register values and incoming bytes.
58 */
59 local void make_crc_table()
60 {
61   uint32_t c;
62   int n, k;
63   uLong poly;		/* polynomial exclusive-or pattern */
64   /* terms of polynomial defining this crc (except x^32): */
65   static const Byte p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26};
66 
67   /* make exclusive-or pattern from polynomial (0xedb88320L) */
68   poly = 0L;
69   for (n = 0; n < sizeof(p)/sizeof(Byte); n++)
70     poly |= 1L << (31 - p[n]);
71 
72   for (n = 0; n < 256; n++)
73   {
74     c = (uLong)n;
75     for (k = 0; k < 8; k++)
76       c = c & 1 ? poly ^ (c >> 1) : c >> 1;
77     crc_table[n] = tole(c);
78   }
79   crc_table_empty = 0;
80 }
81 #else
82 /* ========================================================================
83  * Table of CRC-32's of all single-byte values (made by make_crc_table)
84  */
85 
86 local const uint32_t crc_table[256] = {
87 tole(0x00000000L), tole(0x77073096L), tole(0xee0e612cL), tole(0x990951baL),
88 tole(0x076dc419L), tole(0x706af48fL), tole(0xe963a535L), tole(0x9e6495a3L),
89 tole(0x0edb8832L), tole(0x79dcb8a4L), tole(0xe0d5e91eL), tole(0x97d2d988L),
90 tole(0x09b64c2bL), tole(0x7eb17cbdL), tole(0xe7b82d07L), tole(0x90bf1d91L),
91 tole(0x1db71064L), tole(0x6ab020f2L), tole(0xf3b97148L), tole(0x84be41deL),
92 tole(0x1adad47dL), tole(0x6ddde4ebL), tole(0xf4d4b551L), tole(0x83d385c7L),
93 tole(0x136c9856L), tole(0x646ba8c0L), tole(0xfd62f97aL), tole(0x8a65c9ecL),
94 tole(0x14015c4fL), tole(0x63066cd9L), tole(0xfa0f3d63L), tole(0x8d080df5L),
95 tole(0x3b6e20c8L), tole(0x4c69105eL), tole(0xd56041e4L), tole(0xa2677172L),
96 tole(0x3c03e4d1L), tole(0x4b04d447L), tole(0xd20d85fdL), tole(0xa50ab56bL),
97 tole(0x35b5a8faL), tole(0x42b2986cL), tole(0xdbbbc9d6L), tole(0xacbcf940L),
98 tole(0x32d86ce3L), tole(0x45df5c75L), tole(0xdcd60dcfL), tole(0xabd13d59L),
99 tole(0x26d930acL), tole(0x51de003aL), tole(0xc8d75180L), tole(0xbfd06116L),
100 tole(0x21b4f4b5L), tole(0x56b3c423L), tole(0xcfba9599L), tole(0xb8bda50fL),
101 tole(0x2802b89eL), tole(0x5f058808L), tole(0xc60cd9b2L), tole(0xb10be924L),
102 tole(0x2f6f7c87L), tole(0x58684c11L), tole(0xc1611dabL), tole(0xb6662d3dL),
103 tole(0x76dc4190L), tole(0x01db7106L), tole(0x98d220bcL), tole(0xefd5102aL),
104 tole(0x71b18589L), tole(0x06b6b51fL), tole(0x9fbfe4a5L), tole(0xe8b8d433L),
105 tole(0x7807c9a2L), tole(0x0f00f934L), tole(0x9609a88eL), tole(0xe10e9818L),
106 tole(0x7f6a0dbbL), tole(0x086d3d2dL), tole(0x91646c97L), tole(0xe6635c01L),
107 tole(0x6b6b51f4L), tole(0x1c6c6162L), tole(0x856530d8L), tole(0xf262004eL),
108 tole(0x6c0695edL), tole(0x1b01a57bL), tole(0x8208f4c1L), tole(0xf50fc457L),
109 tole(0x65b0d9c6L), tole(0x12b7e950L), tole(0x8bbeb8eaL), tole(0xfcb9887cL),
110 tole(0x62dd1ddfL), tole(0x15da2d49L), tole(0x8cd37cf3L), tole(0xfbd44c65L),
111 tole(0x4db26158L), tole(0x3ab551ceL), tole(0xa3bc0074L), tole(0xd4bb30e2L),
112 tole(0x4adfa541L), tole(0x3dd895d7L), tole(0xa4d1c46dL), tole(0xd3d6f4fbL),
113 tole(0x4369e96aL), tole(0x346ed9fcL), tole(0xad678846L), tole(0xda60b8d0L),
114 tole(0x44042d73L), tole(0x33031de5L), tole(0xaa0a4c5fL), tole(0xdd0d7cc9L),
115 tole(0x5005713cL), tole(0x270241aaL), tole(0xbe0b1010L), tole(0xc90c2086L),
116 tole(0x5768b525L), tole(0x206f85b3L), tole(0xb966d409L), tole(0xce61e49fL),
117 tole(0x5edef90eL), tole(0x29d9c998L), tole(0xb0d09822L), tole(0xc7d7a8b4L),
118 tole(0x59b33d17L), tole(0x2eb40d81L), tole(0xb7bd5c3bL), tole(0xc0ba6cadL),
119 tole(0xedb88320L), tole(0x9abfb3b6L), tole(0x03b6e20cL), tole(0x74b1d29aL),
120 tole(0xead54739L), tole(0x9dd277afL), tole(0x04db2615L), tole(0x73dc1683L),
121 tole(0xe3630b12L), tole(0x94643b84L), tole(0x0d6d6a3eL), tole(0x7a6a5aa8L),
122 tole(0xe40ecf0bL), tole(0x9309ff9dL), tole(0x0a00ae27L), tole(0x7d079eb1L),
123 tole(0xf00f9344L), tole(0x8708a3d2L), tole(0x1e01f268L), tole(0x6906c2feL),
124 tole(0xf762575dL), tole(0x806567cbL), tole(0x196c3671L), tole(0x6e6b06e7L),
125 tole(0xfed41b76L), tole(0x89d32be0L), tole(0x10da7a5aL), tole(0x67dd4accL),
126 tole(0xf9b9df6fL), tole(0x8ebeeff9L), tole(0x17b7be43L), tole(0x60b08ed5L),
127 tole(0xd6d6a3e8L), tole(0xa1d1937eL), tole(0x38d8c2c4L), tole(0x4fdff252L),
128 tole(0xd1bb67f1L), tole(0xa6bc5767L), tole(0x3fb506ddL), tole(0x48b2364bL),
129 tole(0xd80d2bdaL), tole(0xaf0a1b4cL), tole(0x36034af6L), tole(0x41047a60L),
130 tole(0xdf60efc3L), tole(0xa867df55L), tole(0x316e8eefL), tole(0x4669be79L),
131 tole(0xcb61b38cL), tole(0xbc66831aL), tole(0x256fd2a0L), tole(0x5268e236L),
132 tole(0xcc0c7795L), tole(0xbb0b4703L), tole(0x220216b9L), tole(0x5505262fL),
133 tole(0xc5ba3bbeL), tole(0xb2bd0b28L), tole(0x2bb45a92L), tole(0x5cb36a04L),
134 tole(0xc2d7ffa7L), tole(0xb5d0cf31L), tole(0x2cd99e8bL), tole(0x5bdeae1dL),
135 tole(0x9b64c2b0L), tole(0xec63f226L), tole(0x756aa39cL), tole(0x026d930aL),
136 tole(0x9c0906a9L), tole(0xeb0e363fL), tole(0x72076785L), tole(0x05005713L),
137 tole(0x95bf4a82L), tole(0xe2b87a14L), tole(0x7bb12baeL), tole(0x0cb61b38L),
138 tole(0x92d28e9bL), tole(0xe5d5be0dL), tole(0x7cdcefb7L), tole(0x0bdbdf21L),
139 tole(0x86d3d2d4L), tole(0xf1d4e242L), tole(0x68ddb3f8L), tole(0x1fda836eL),
140 tole(0x81be16cdL), tole(0xf6b9265bL), tole(0x6fb077e1L), tole(0x18b74777L),
141 tole(0x88085ae6L), tole(0xff0f6a70L), tole(0x66063bcaL), tole(0x11010b5cL),
142 tole(0x8f659effL), tole(0xf862ae69L), tole(0x616bffd3L), tole(0x166ccf45L),
143 tole(0xa00ae278L), tole(0xd70dd2eeL), tole(0x4e048354L), tole(0x3903b3c2L),
144 tole(0xa7672661L), tole(0xd06016f7L), tole(0x4969474dL), tole(0x3e6e77dbL),
145 tole(0xaed16a4aL), tole(0xd9d65adcL), tole(0x40df0b66L), tole(0x37d83bf0L),
146 tole(0xa9bcae53L), tole(0xdebb9ec5L), tole(0x47b2cf7fL), tole(0x30b5ffe9L),
147 tole(0xbdbdf21cL), tole(0xcabac28aL), tole(0x53b39330L), tole(0x24b4a3a6L),
148 tole(0xbad03605L), tole(0xcdd70693L), tole(0x54de5729L), tole(0x23d967bfL),
149 tole(0xb3667a2eL), tole(0xc4614ab8L), tole(0x5d681b02L), tole(0x2a6f2b94L),
150 tole(0xb40bbe37L), tole(0xc30c8ea1L), tole(0x5a05df1bL), tole(0x2d02ef8dL)
151 };
152 #endif
153 
154 #if 0
155 /* =========================================================================
156  * This function can be used by asm versions of crc32()
157  */
158 const uint32_t * ZEXPORT get_crc_table()
159 {
160 #ifdef DYNAMIC_CRC_TABLE
161   if (crc_table_empty) make_crc_table();
162 #endif
163   return (const uint32_t *)crc_table;
164 }
165 #endif
166 
167 /* ========================================================================= */
168 # if __BYTE_ORDER == __LITTLE_ENDIAN
169 #  define DO_CRC(x) crc = tab[(crc ^ (x)) & 255] ^ (crc >> 8)
170 # else
171 #  define DO_CRC(x) crc = tab[((crc >> 24) ^ (x)) & 255] ^ (crc << 8)
172 # endif
173 
174 /* ========================================================================= */
175 
176 /* No ones complement version. JFFS2 (and other things ?)
177  * don't use ones compliment in their CRC calculations.
178  */
179 uint32_t ZEXPORT crc32_no_comp(uint32_t crc, const Bytef *buf, uInt len)
180 {
181     const uint32_t *tab = crc_table;
182     const uint32_t *b =(const uint32_t *)buf;
183     size_t rem_len;
184 #ifdef DYNAMIC_CRC_TABLE
185     if (crc_table_empty)
186       make_crc_table();
187 #endif
188     crc = cpu_to_le32(crc);
189     /* Align it */
190     if (((long)b) & 3 && len) {
191 	 uint8_t *p = (uint8_t *)b;
192 	 do {
193 	      DO_CRC(*p++);
194 	 } while ((--len) && ((long)p)&3);
195 	 b = (uint32_t *)p;
196     }
197 
198     rem_len = len & 3;
199     len = len >> 2;
200     for (--b; len; --len) {
201 	 /* load data 32 bits wide, xor data 32 bits wide. */
202 	 crc ^= *++b; /* use pre increment for speed */
203 	 DO_CRC(0);
204 	 DO_CRC(0);
205 	 DO_CRC(0);
206 	 DO_CRC(0);
207     }
208     len = rem_len;
209     /* And the last few bytes */
210     if (len) {
211 	 uint8_t *p = (uint8_t *)(b + 1) - 1;
212 	 do {
213 	      DO_CRC(*++p); /* use pre increment for speed */
214 	 } while (--len);
215     }
216 
217     return le32_to_cpu(crc);
218 }
219 #undef DO_CRC
220 
221 uint32_t ZEXPORT crc32 (uint32_t crc, const Bytef *p, uInt len)
222 {
223      return crc32_no_comp(crc ^ 0xffffffffL, p, len) ^ 0xffffffffL;
224 }
225 
226 /*
227  * Calculate the crc32 checksum triggering the watchdog every 'chunk_sz' bytes
228  * of input.
229  */
230 uint32_t ZEXPORT crc32_wd (uint32_t crc,
231 			   const unsigned char *buf,
232 			   uInt len, uInt chunk_sz)
233 {
234 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
235 	const unsigned char *end, *curr;
236 	int chunk;
237 
238 	curr = buf;
239 	end = buf + len;
240 	while (curr < end) {
241 		chunk = end - curr;
242 		if (chunk > chunk_sz)
243 			chunk = chunk_sz;
244 		crc = crc32 (crc, curr, chunk);
245 		curr += chunk;
246 		WATCHDOG_RESET ();
247 	}
248 #else
249 	crc = crc32 (crc, buf, len);
250 #endif
251 
252 	return crc;
253 }
254 
255 void crc32_wd_buf(const unsigned char *input, unsigned int ilen,
256 		unsigned char *output, unsigned int chunk_sz)
257 {
258 	uint32_t crc;
259 
260 	crc = crc32_wd(0, input, ilen, chunk_sz);
261 	crc = htonl(crc);
262 	memcpy(output, &crc, sizeof(crc));
263 }
264